The present invention relates generally to storage battery ventilation, and more particularly, to an improved vent for use in connection with storage battery designs.
As a result of various chemical processes which occur when storage batteries are in use, as well as during the charging of such storage batteries, gases such as hydrogen and oxygen are often produced. Such gases are generally vented to the atmosphere in order to relieve the battery of internal pressures which would otherwise result. In performing such ventilation, the following two factors should be considered.
First of all, since the gases being vented are hydrogen and oxygen, care must be taken to avoid the possibility of igniting such gases. This is particularly so during battery charging, since gassing becomes more prevalent during such periods, and since electrical connections made to the terminals of the battery can create a potential for sparks. Under such conditions battery damage can result from sparks or ignited gases reentering the battery, at times resulting in battery explosion.
Secondly, care must be taken to prevent the loss of battery electrolyte through the vent, either as a result of misting which occurs in connection with battery gassing, or as a result of battery movement. Those skilled in the art recognize that use of electrolyte preservation venting means reduces the need for additional servicing procedures and often prevents electrolyte loss which may compromise the service life of the battery. However, battery electrolyte levels must be carefully monitored and replenished, as needed.
A variety of devices have been developed in an attempt to accommodate the foregoing by providing a vent cap which improves both safe and reliable in operation, yet inexpensive to manufacture. In an effort to prevent sparks and ignited gases from reentering the battery, many vent caps are generally provided with proportioned apertures or slits which are sufficiently large to enable ventilation of gases from the battery, yet which are sufficiently small to limit the passage of sparks or ignited gases. To reduce the loss of electrolyte, such vent caps are generally provided with baffles or passageways which develop relatively contorted flow paths designed to condense and facilitate the return of electrolyte collected within the vent cap to the cell of the battery with which the vent cap is associated.
U.S. Pat. No. 4,517,262, issued May 14, 1985, to Beidler and commonly assigned, discloses a vent for a storage battery which significantly contributes to the solutions of the problems outlined above. The present invention provides improved solutions by employing a baffle system which enhances electrolyte retention where electrolyte pumping occurs in battery use, and concurrently offers manufacturing feasibility through simplicity of production.